Method of explosive welding of metal plates

ABSTRACT

Metal plates are welded together by spacing base plates apart in a horizontal row and interdigitating pairs of plates to be welded to the base plates along with explosive charges which are placed between the plates of the pairs.

United States Patent Demchuk et a1.

[ Mar. 21, 1972 [54] METHOD OF EXPLOSIVE WELDING OF METAL PLATES [72]lnventors: Alexandr Fedorovlch Demchuk,

Akademicheskoya ulitsa 25, kv. 47; Andrei Andreevlch Deribas, ulitsaPravdy, 1, kb. 20, both of Novosibirsk; Vladimir Mikhailovich Kudinov,ulitsa Filatova l/22, kv, 5 l Kiev; Felix Iovich Matveenkov, ulitsaPrandy, I, kv. 24; Valery Alexandrovich Simonov, bulvar Molo'dezhi, 30,kv. 19, both of Novosibirsk, all of Eli-75.34.. r

[22] Filed: Aug. 15,1969

[2]] Appl.No.: 850,382

[52] US. Cl ..29/470.l, 29/486, 29/4975 [51] Int. Cl ..B23k 21/00 [58]Field of Search ..29/470. 1 486, 421 E, 497.5

[56] References Cited UNITED STATES PATENTS R e 2i8 5 4/1970 Chudzik..29/470.1 3,474,520 10/1969 Takizawa et al ....29/470.1 3,434,1973/1969 Davenport ....29/470.l 3,419,951 1/1969 Carls0n..... ....29/470.l3,417,455 12/1968 Pearson ....29/470.l 3,377,693 4/1968 Fukumoto....29/470.1 3,346,946 10/1967 Riegelmayer ..29/470.l 3,233,312 2/1966Cowan et a1. ..29/470.l X 3,140,537 7/1964 Popoff ..29/421 X PrimaryExaminer.lohn F. Campbell Assistant ExaminerRonald .1. ShoreAttorney-Waters, Roditi, Schwartz & Nissen [57] ABSTRACT Metal platesare welded together by spacing base plates apart in a horizontal row andinterdigitating pairs of plates to be welded to the base plates alongwith explosive charges which are placed between the plates of the pairs.

54 Claims, 8 Drawing Figures PATENTEU R 21 I972 SHEET 2 OF 2 .H Y W/////PIE. 7

METHOD OF EXPLOSIVE WELDING OE METAL PLATES The present inventionrelates to welding practices and to the production of multilayermaterials, and more specifically to methods for the explosive welding ofmetals, and to methods of obtaining doubleand multilayer metal platesand various multilayer products used in the chemical, electronic,atomic, missile and other engineering fields.

Known in the art are methods further explosive welding of metal plateswhich provide for explosive welding of one or several plates to one basemetal plate in one operation.

These methods, however, do not insure adequate productivity and inconsiderable consumption of explosives, as well as insufficient qualityof the multilayer plates obtained Accordingly, they do not comply withindustrial requirements.

An object of the present invention is to provide a simple and highlyefficient method further explosive welding of metal plates, that permitsobtaining several doubleor multilayer metal plates in one operation.Another object of the present invention is to insure a considerableeconomy of explosives.

Still another object of the invention is to raise the quality of themultilayer metal plates obtained.

In accordance with the above and other objects, in the method for theexplosive welding of metal plates according to the invention severalbase plates are set edgewise at least in one horizontal row, theirwelding sides facing each other at a certain distance and in each gapbetween these plates with certain clearances therefrom at least twoplates to be welded on, having no contact with one another, are placededgewise, their welding sides facing the base plates, explosive chargescommon for the plates to be welded on are placed therebetween whereuponall the explosive charges in at least one row are simultaneouslyinitiated.

It is advisable that the base plates set edgewise in at least onehorizontal row should be arranged in pairs, their nonwelding surfacescontacting each other.

It is preferred that the plates to be welded on should be locatedbetween the base plates at a certain angle to the latter from the placeof charge initiation in the direction of the detonation frontpropagation.

It is advantageous that at least two plates to be welded on should havetheir portions closest to the base plates bent off towards the latter,and an explosive of greater power be placed between these bent offportions as compared to that placed between the remaining noncontactingportions of the plates to be welded on, and then all the explosivecharges be initiated simultaneously from the side of the bent offportions of theplates to be welded on, in at least one row.

In the plates to be welded on their corners closest to the base platesare advisable bent off towards the latter.

The bent off portions of the plates to be welded on are desirablydeflected to an angle of 4 to 12 depending on the detonation rate of theexplosive of greater power.

These bent off portions advisably have a length 8 to 12 times as greatas the thickness of the plate to be welded on, in the direction of thedetonation front propagation.

The layer of the explosive of greater power between the bent off partsof the plates to be welded on is desirably uniformly reduced inthickness from the place of initiation to the beginning of the explosivecharge between the remaining portions of said plates.

The thickness of layers of the explosive can be uniformly decreased byabout one-third thereof from the place of charge initiation in thedirection of the detonation front propagation.

The base plates and the plates to be welded on are advisably located inparallel to each other, and between the plates to be welded on explosivecharges should be placed whose rate of detonation does not exceed soundpropagation velocity in the metals ofsaid plates.

When welding together metal plates made of brittle metals it ispreferable to preheat them.

On the welding surfaces of the base metal plates depressions can be madeto be filled with a lower-melting metal, for instance, tin, and after atleast one plate to be welded on is joined by the explosion method to thewelding surface of each said base plate, the low-melting metal should befused out from the cavities formed between the plates welded together.

On the welding surfaces of the base metal plates depressions can be madeto be filled, alternatively, with a soluble material, for instance,sodium chloride, and after at least one plate to be welded on is joinedby the explosion method to the welding surface of each said base plate,the soluble material should be removed from the cavities formed betweenthe plates welded together.

One additional thin metal sheet is desirably prewelded by the explosionmethod to the welding surfaces of each base plate with filleddepressions.

Other objects and advantages of the present invention will becomeapparent from the following description with reference to theaccompanying drawings, wherein:

FIG. 1 illustrates schematically, in accordance with the invention,several base plates and plates to be welded on together with theexplosive charges, all placed edgewise in one row, the arrangement beingshown in side view (longitudinal section);

FIG. .2 is a top view of the arrangement of FIG. 1;

FIG. 3 is a view similar to FIG. 1, the base plates being arranged inpairs, their non-welding surfaces contacting each other;

FIG. 4 is a top view of the arrangement of FIG. 3;

FIG. 5 is a top view of plates to be welded on, with bent off parts andthe explosive charge therebetween, all located between the base plates;

FIG. 6 is a view similar to FIG. 5 showing bent off corners (theexplosive charge not being shown);

FIG. 7 shows the plates to be welded on and the base plates havingdepressions filled with a low-melting metal or a soluble material, theview being a longitudinal section across the depressions;

FIG. 8 is a view similar to FIG. 7 with an additional thin metal sheetprewelded to each base metal plate by the explosive method.

Explosive welding of metal plates according to the invention is carriedout as follows.

Several base plates 1 (FIGS. 1 and 2) are, in accordance with theinvention, placed edgewise on footing 2 in at least one horizontal row,their welding sides facing each other at a certain distance. In each gapbetween the base plates 1 with certain clearances therefrom at least twoplates 3 to be welded on, having no contact with one another, are placededgewise as well, their welding sides facing said base plates, whilebeside each extreme base plate in the said row at least one plate to bewelded on is placed, also edgewise. Between plates 3 to be welded on,common explosive charges 4 are placed, the explosive charges used on theextreme plates to be welded on having a power equal to that of thecharges used between the plates to be welded on. All the explosivecharges 4 are simultaneously set off by one detonator 5, whoseinitiating pulse is transmitted to each explosive charge 4 throughpieces of detonating cord 6 of equal length.

As a result of explosive welding according to the described procedureplates 3 are welded simultaneously to each base plate 1, one on eitherside thereof.

To weld plates 3 to only one side of each base plate 1, the latter areagain set edgewise (FIGS. 3 and 4) in at least one horizontal row, andare arranged in pairs, so that their nonwelding surfaces contact eachother.

Plates 3 to be welded on (FIGS. 1-4) are placed between the base plates1 at a certain angle to the latter from the initia tion place of theexplosive charge 4 in the direction of the detonation front propagation.The thickness of the layer of the explosive charges 4 located betweenplates 3 to be welded on is uniformly decreased from the place ofinitiation of the charges in the direction of the detonation frontpropagation. The value of the reduced layer thickness of the explosivecharges 4 should be about one-third of the initial charge thickness.However, in case of small thickness of plates 3 to be welded on, it isadvisable to place the explosive charges 4 between plates 3 in uniformlayers.

When welding base plates 1 with plates 3 of considerable thickness (5mm. and more), to improve the quality of welding in the initial portionof the weld, plates 3 to be welded on have their portions 7 (FIG. 5)closest to the base plates 1 bent off towards the latter. Placed betweenthe bent off portions 7 of plates 3 to be welded on is an explosive ofgreater power than that placed between the remaining portions of theseplates. The explosive charges 4 are initiated from the side of the morepowerful explosive 8.

In some cases it is advisable that plates 3 to be welded on should havetheir corners 9 (FIG. 6) closest to the base plates 1 bent off towardsthe latter, a more powerful explosive (not shown in FIG. 6) being againplaced between these bent off corners.

Portions 7 or corners 9 of plates 3 to be welded on are bent off towardsthe base plates 1 to an angle of4 to 12 depending on the detonation rateof the explosive of greater power and the thickness ofthe plates to bewelded on.

Portions 7 or corners 9 of plates 3 to be welded on are bent off over alength 8 to 12 times as great as the thickness of said plates in thedirection of the detonation front propagation.

The thickness of the layer of explosive 8 of greater power between thebent off portions 7 or corners 9 of plates 3 to be welded on isadvisably uniformly reduced from the place ofinitiation to the beginningof the explosive charge 4 between the remaining portions of the platesto be welded on.

In some cases the base plates 1 and plates 3 to be welded on are setparallel to one another (not shown in the drawings), the explosivecharges used between plates 3 then having a rate of detonation that doesnot exceed sound propagation velocity in the metals of plates to bewelded together.

When welding together metal plates made of brittle metals, they arepreheated to insure a quality joint.

To obtain welded products with internal cavities, depressions 10 ofrequired shape are formed on the welding surfaces of the base plates 1to be then filled with a low-melting metal 11 or a soluble material 11.Tin, lead, their alloys, various salts and other materials may be usedas fillers.

To the welding surfaces of the base plates 1 thus prepared plates 3 areexplosion-welded, after which the filler is removed from the cavitiesformed between the plates welded together.

To prevent breakage of plates 3 to be welded on when their thickness isover 5 mm., it is advisable to preweld, by the explosion technique, oneadditional thin metal sheet 12 (FIG. 8) to each welding surface of thebase plates 1.

In all the above-described cases several plates 3 can be weldedsimultaneously to each base plate 1 (not shown in the drawings). In thiscase the explosive charge 4 is located between those two adjacent plates3 to be welded on that are most distant from their respective baseplates 1.

The described method is mainly advisable for the cases when the baseplates 1 are of considerable thickness.

Explosive welding of metal plates according to the invention has thefollowing advantages.

Setting of the base plates 1 and plates 3 to be welded thereon edgewisein a row permits obtaining in one operation, a considerable number ofmultilayer metal plates, and makes possible mechanization of assemblyoperations in factory conditions (mounting of base plates and plates tobe welded on), which fact sharply raises the productivity, a highquality of weld joints being insured.

Welding two or several plates 3 to two base plates by one commonexplosive charge 4 raises the explosion efficiency 1.5 to 5 times.

Symmetrical load distribution in explosion welding rule out any saggingof the base plates 1, substantially facilitating further working of thelatter.

We claim:

1. A method for the explosive welding of metal plates, said methodcomprising setting at least two metal base plates on their edge in atleast one horizontal row with the surfaces of the plates to which a weldis to be effected facing each other and spaced from each other to format least one gap, and in each gap between said plates placing by settingon their edge at least two metal plates to be welded on, spaced from oneanother and at least in part from the corresponding base plates, withthe welding surfaces thereof facing the base plates, placing between theplates to be welded on in each gap explosive charges common thereto,placing explosive charges outside of the endmost of said base plates ineach said horizontal row, and simultaneously firing the explosivecharges in at least one said row explosively weld said plates to bewelded on to said base plates.

2. A method according to claim 1, wherein the base plates in at leastone horizontal row are arranged in pairs with their non-welding surfacesin contact with each other.

3. A method as set forth in claim I, wherein the plates to be welded onare located between the base plates at an angle to the latter.

4. A method as defined in claim 2, wherein the plates to be welded onare located between the base plates at an angle to the latter.

5. A method according to claim 1, wherein at least two plates to bewelded on have portions which are closest to the base plates and whichare bent towards the latter, comprising placing between the bent offportions of the plates to be welded on an explosive of greater powerthan that between the remaining portions of the plates to be welded on,firing of the explosive charges being simultaneously initiated startingwith the explosive of greater power.

6. A method, as claimed in claim 2, wherein at least two plates to bewelded on have portions which are closest to the base plates and whichare bent towards the latter, comprising placing between the bent offportions of the plates to be welded on an explosive of greater powerthan that between the remaining portions of the plates to be welded on,firing of the explosive charges being simultaneously initiated startingwith the explosive of greater power.

7. A method as set forth in claim 3, wherein at least two plates to bewelded on have portions which are closest to the base plates and whichare bent towards the latter, comprising placing between the bent offportions of the plates to be welded on an explosive of greater powerthan that between the remaining portions of the plates to be welded onfiring of the explosive charges being simultaneously initiated startingwith the explosive of greater power.

8. A method according to claim 5, wherein the plates to be welded onhave corners which are closest to the base plates and which are benttowards the latter.

9. A method according to claim 5, wherein the bent portions of theplates to be welded on are bent towards the base plates at an angle of 4to 12 depending on the detonation rate of the explosive of greaterpower.

10. A method as claimed in claim 8, wherein the bent corners of theplates to be welded on are bent towards the base plates at an angle of 4to 12 depending on the detonation rate of the explosive of greaterpower.

11. A method as claimed in claim 5, wherein the explosive charges arecharacterized by a direction of detonation front propagation and thebent portions of the plates to be welded on are bent over a lengthequaling 8 to 12 times the thickness of said plates in the direction ofthe detonation front propagation.

12. A method as set forth in claim 8 wherein the explosive charges arecharacterized by a direction of detonation front propagation and thebent corners of the plates to be welded on are bent over a lengthequaling 8 to 12 times the thickness of said plates in the direction ofthe detonation front propagation.

13. A method as defined in claim 9, wherein the explosive charges arecharacterized by a direction of detonation front propagation and thebent portions of the plates to be welded on are bent over a lengthequaling 8 to 12 times the thickness of said plates in the direction ofthe detonation front propagation.

14. A method according to claim 5, wherein the thickness of the layer ofthe explosive of greater power used between the bent portions of theplates to be welded on is uniformly reduced from the place of initiationto the beginning of the explosive charge between the remaining portionsof said plates.

15. A method as defined in claim 8, wherein the thickness of the layerof the explosive of greater power used between the bent corners of theplates to be welded on is uniformly reduced from the place of initiationto the beginning of the explosive charge between the remaining portionsof said plates.

16. A method as defined in claim 9, wherein the thickness of the layerof the explosive of greater power used between the bent portions of theplates to be welded on is uniformly reduced from the place of initiationto the beginning of the explosive charge between the remaining portionssaid plates.

17. A method as claimed in claim 11, wherein the thickness of the layerof the explosive of greater power used between the bent portions of theplates to be welded on is uniformly reduced from the place ofinitiationto the beginning of the explosive charge between the remaining portionsof said plates.

18. A method as set forth in claim 3, wherein the explosive charges arecharacterized by a direction of detonation front propagation and thelayer thicknesses of the explosives are uniformly reduced by aboutone-third thereof from the place of initiation in the direction of thedetonation front propagation.

19. A method as set forth in claim 1, wherein the base plates and theplates to be welded on are set parallel to one another, and selectingexplosive charges whose rate of detonation does not exceed soundpropagation velocity in said plates.

20. A method as claimed in claim 2, wherein the base plates and theplates to be welded on are set parallel to one another, and selectingexplosive charges, whose rate of detonation does not exceed soundpropagation velocity in plates.

21. A method as set forth in claim 1, wherein before welding togethermetal plates made of brittle metals these plates are preheated.

22. A method as defined in claim 2, wherein before welding togethermetal plates made of brittle metals, these plates are preheated.

23. A method according to claim 3, wherein before welding together metalplates made of brittle metals these plates are preheated.

24. A method according to claim 5, wherein before welding together metalplates made of brittle metals these plates are preheated.

25. A method according to claim 8, wherein before welding together metalplates made of brittle metals these plates are preheated.

26. A method according to claim 9, wherein before welding together metalplates made of brittle metals these plates are preheated.

27. A method according to claim 11, wherein before welding togethermetal plates made of brittle metals these plates are preheated.

28. A method according to claim 14, wherein before welding togethermetal plates made of brittle metals these plates are preheated.

29. A method according to claim 19, wherein before welding togethermetal plates made of brittle metals these plates are preheated.

30. A method according to claim 20, wherein before welding togethermetal plates made of brittle metals these plates are preheated.

31. A method as claimed in claim 1, comprising forming depressions inthe welding surfaces of the base metal plates and filling saiddepressions with a lower-melting metal, and after welding fusing out thelow-melting metal.

32. A method as claimed in claim 2, comprising forming depressions inthe welding surfaces of the base metal plates and filling saiddepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

33. A method as claimed in claim 3, comprising forming depressions inthe welding surfaces of the base metal plates and filling saiddepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

34. A method as set forth in claim 5, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

35. A method as set forth in claim 8, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

36. A method as set forth in claim 9, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

37. A method as claimed in claim 11, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

38. A method as claimed in claim 14, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

39. A method as claimed in claim 19, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

40. A method as claimed in claim 20, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

41. A method as claimed in claim 21, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a lower-melting metal, and after welding fusing out thelower-melting metal.

42. A method as claimed in claim 1, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

43. A method according to claim 2, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a soluble material, and after welding removing said solublematerial.

44. A method according to claim 3, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a soluble material, and after welding removing said solublematerial.

45. A method according to claim 5, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a soluble material, and after welding removing said solublematerial.

46. A method as defined in claim 8, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

47. A method as defined in claim 9, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

48. A method as defined in claim 11, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

49. A method as set forth in claim 14, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

50. A method as set forth in claim 19, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

51. A method as set forth in claim 20, comprising forming depressions inthe welding surfaces of the base metal plates and filling thedepressions with a soluble material, and after welding removing saidsoluble material.

52. A method according to claim 21, comprising forming depressions inthe welding surfaces of the base metal plates loo

1. A method for the explosive welding of metal plates, said methodcomprising setting at least two metal base plates on their edge in atleast one horizontal row with the surfaces of the plates to which a weldis to be effected facing each other and spaced from each other to format least one gap, and in each gap between said plates placing by settingon their edge at least two metal plates to be welded on, spaced from oneanother and at least in part from the corresponding base plates, withthe welding surfaces thereof facing the base plates, placing between theplates to be welded on in each gap explosive charges common thereto,placing explosive charges outside of the endmost of said base plates ineach said horizontal row, and simultaneously firing the explosivecharges in at least one said row explosively weld said plates to bewelded on to said base plates.
 2. A method according to claim 1, whereinthe base plates in at least one horizontal row are arranged in pairswith their non-welding surfaces in contact with each other.
 3. A methodas set forth in claim 1, wherein the plates to be welded on are locatedbetween the base plates at an angle to the latter.
 4. A method asdefined in claim 2, wherein the plates to be welded on are locatedbetween the base plates at an angle to the latter.
 5. A method accordingto claim 1, wherein at least two plates to be welded on have portionswhich are closest to the base plates and which are bent towards thelatter, comprising placing between the bent off portions of the platesto be welded on an explosive of greater power than that between theremaining portions of the plates to be welded on, firing of theexplosive charges being simultaneously initiated starting with theexplosive of greater power.
 6. A method, as claimed in claim 2, whereinat least two plates to be welded on have portions which are closest tothe base plates and which are bent towards the latter, comprisingplacing between the bent off portions of the plates to be welded on anexplosive of greater power than that between the remaining portions ofthe plates to be welded on, firing of the explosive charges beingsimultaneously initiated starting with the explosive of greater power.7. A method as set forth in claim 3, wherein at least two plates to bewelded on have portions which are closest to the base plates and whichare bent towards the latter, comprising placing between the bent offportions of the plates to be welded on an explosive of greater powerthan that between the remaining portions of the plates to be welded onfiring of the explosive charges being simultaneously initiated startingwith the explosive of greater power.
 8. A method according to claim 5,wherein the plates to be welded on have corners which are closest to thebase plates and which are bent towards the latter.
 9. A method accordingto claim 5, wherein the bent portions of the plates to be welded on arebent towards the base plates at an angle of 4* to 12* depending on thedetonation rate of the explosive of greater power.
 10. A method asclaimed in claim 8, wherein the bent corners of the plates to be weldedon are bent towards the base plates at an angle of 4* to 12* dependingon the detonation rate of the explosive of greater power.
 11. A methodas claimed in claim 5, wherein the explosive charges are characterizedby a direction of detonation front propagation and the bent portions ofthe plates to be welded on are bent over a length equaling 8 to 12 timesthe thickness of said plates in the direction of the detonation frontpropagation.
 12. A method as set forth in claim 8 wherein the explosivecharges are characterized by a direction of detonation front propagationand the bent corners of the plates to be welded on are bent over alength equaling 8 to 12 times the thickness of said plates in thedirection of the detonation front propagation.
 13. A method as definedin claim 9, wherein the explosive charges are characterized by adirection of detonation front propagation and the bent portions of theplates to be welded on are bent over a length equaling 8 to 12 times thethickness of said plates in the direction of the detonation frontpropagation.
 14. A method according to claim 5, wherein the thickness ofthe layer of the explosive of greater power used between the bentportions of the plates to be welded on is uniformly reduced from theplace of initiation to the beginning of the explosive charge between theremaining portions of said plates.
 15. A method as defined in claim 8,wherein the thickness of the layer of the explosive of greater powerused between the bent corners of the plates to be welded on is uniformlyreduced from the place of initiation to the beginning of the explosivecharge between the remaining portions of said plates.
 16. A method asdefined in claim 9, wherein the thickness of the layer of the explosiveof greater power used between the bent portions of the plates to bewelded on is uniformly reduced from the place of initiation to thebeginning of the explosive charge between the remaining portions saidplates.
 17. A method as claimed in claim 11, wherein the thickness ofthe layer of the explosive of greater power used between the bentportions of the plates to be welded on is uniformly reduced from theplace of initiation to the beginning of the explosive charge between theremaining portions of said plates.
 18. A method as set forth in claim 3,wherein the explosive charges are characterized by a direction ofdetonation front propagation and the layer thicknesses of the explosivesare uniformly reduced by about one-third thereof from the place ofinitiation in the direction of the detonation front propagation.
 19. Amethod as set forth in claim 1, wherein the base plates and the platesto be welded on are set parallel to one another, and selecting explosivecharges whose rate of detonation does not exceed sound propagationvelocity in said plates.
 20. A method as claimed in claim 2, wherein thebase plates and the plates to be welded on are set parallel to oneanother, and selecting explosive charges, whose rate of detonation doesnot exceed sound propagation velocity in plates.
 21. A method as setforth in claim 1, wherein before welding together metal plates made ofbrittle metals these plates are preheated.
 22. A method as defined inclaim 2, wherein before welding Together metal plates made of brittlemetals, these plates are preheated.
 23. A method according to claim 3,wherein before welding together metal plates made of brittle metalsthese plates are preheated.
 24. A method according to claim 5, whereinbefore welding together metal plates made of brittle metals these platesare preheated.
 25. A method according to claim 8, wherein before weldingtogether metal plates made of brittle metals these plates are preheated.26. A method according to claim 9, wherein before welding together metalplates made of brittle metals these plates are preheated.
 27. A methodaccording to claim 11, wherein before welding together metal plates madeof brittle metals these plates are preheated.
 28. A method according toclaim 14, wherein before welding together metal plates made of brittlemetals these plates are preheated.
 29. A method according to claim 19,wherein before welding together metal plates made of brittle metalsthese plates are preheated.
 30. A method according to claim 20, whereinbefore welding together metal plates made of brittle metals these platesare preheated.
 31. A method as claimed in claim 1, comprising formingdepressions in the welding surfaces of the base metal plates and fillingsaid depressions with a lower-melting metal, and after welding fusingout the low-melting metal.
 32. A method as claimed in claim 2,comprising forming depressions in the welding surfaces of the base metalplates and filling said depressions with a lower-melting metal, andafter welding fusing out the lower-melting metal.
 33. A method asclaimed in claim 3, comprising forming depressions in the weldingsurfaces of the base metal plates and filling said depressions with alower-melting metal, and after welding fusing out the lower-meltingmetal.
 34. A method as set forth in claim 5, comprising formingdepressions in the welding surfaces of the base metal plates and fillingthe depressions with a lower-melting metal, and after welding fusing outthe lower-melting metal.
 35. A method as set forth in claim 8,comprising forming depressions in the welding surfaces of the base metalplates and filling the depressions with a lower-melting metal, and afterwelding fusing out the lower-melting metal.
 36. A method as set forth inclaim 9, comprising forming depressions in the welding surfaces of thebase metal plates and filling the depressions with a lower-meltingmetal, and after welding fusing out the lower-melting metal.
 37. Amethod as claimed in claim 11, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a lower-melting metal, and after welding fusing out thelower-melting metal.
 38. A method as claimed in claim 14, comprisingforming depressions in the welding surfaces of the base metal plates andfilling the depressions with a lower-melting metal, and after weldingfusing out the lower-melting metal.
 39. A method as claimed in claim 19,comprising forming depressions in the welding surfaces of the base metalplates and filling the depressions with a lower-melting metal, and afterwelding fusing out the lower-melting metal.
 40. A method as claimed inclaim 20, comprising forming depressions in the welding surfaces of thebase metal plates and filling the depressions with a lower-meltingmetal, and after welding fusing out the lower-melting metal.
 41. Amethod as claimed in claim 21, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a lower-melting metal, and after welding fusing out thelower-melting metal.
 42. A method as claimed in claim 1, comprisingforming depressions in the welding surfaces of the base metal plates andfilling the depressions with a soluble material, and after weldingremoving said soluble material.
 43. A method according to claim 2,comprising forming depressions in the welding surfaces of the base metalplates and filling thE depressions with a soluble material, and afterwelding removing said soluble material.
 44. A method according to claim3, comprising forming depressions in the welding surfaces of the basemetal plates and filling the depressions with a soluble material, andafter welding removing said soluble material.
 45. A method according toclaim 5, comprising forming depressions in the welding surfaces of thebase metal plates and filling the depressions with a soluble material,and after welding removing said soluble material.
 46. A method asdefined in claim 8, comprising forming depressions in the weldingsurfaces of the base metal plates and filling the depressions with asoluble material, and after welding removing said soluble material. 47.A method as defined in claim 9, comprising forming depressions in thewelding surfaces of the base metal plates and filling the depressionswith a soluble material, and after welding removing said solublematerial.
 48. A method as defined in claim 11, comprising formingdepressions in the welding surfaces of the base metal plates and fillingthe depressions with a soluble material, and after welding removing saidsoluble material.
 49. A method as set forth in claim 14, comprisingforming depressions in the welding surfaces of the base metal plates andfilling the depressions with a soluble material, and after weldingremoving said soluble material.
 50. A method as set forth in claim 19,comprising forming depressions in the welding surfaces of the base metalplates and filling the depressions with a soluble material, and afterwelding removing said soluble material.
 51. A method as set forth inclaim 20, comprising forming depressions in the welding surfaces of thebase metal plates and filling the depressions with a soluble material,and after welding removing said soluble material.
 52. A method accordingto claim 21, comprising forming depressions in the welding surfaces ofthe base metal plates and filling the depressions with a solublematerial, and after welding removing said soluble material.
 53. A methodaccording to claim 31, wherein one additional thin metal sheet is firstwelded by explosion to each welding surface of the base plates with thefilled depressions.
 54. A method according to claim 42, wherein oneadditional thin metal sheet is first welded by explosion to each weldingsurface of the base plates with the filled depressions.